This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To define the influence of specific extracellular matrix components on trophoblast differentiation from human embryonic [unreadable] stem cells.[unreadable] [unreadable] We have previously demonstrated that human embryonic stem cells are able to differentiate into trophoblasts upon [unreadable] embryoid body formation, and that 3-dimensional culture in the complex mixture Matrigel supports enhanced [unreadable] differentiated function. To work towards defining the factors and pathways that control placental morphogenesis, we have [unreadable] cultured embryoid bodies on surfaces of biochemically pure collagen IV, laminin, fibronectin, hydrolyzed collagen I, or [unreadable] serum-coated dishes. The profiles of the secretion of chorionic gonadotropin and the metabolic activity of the cellular [unreadable] outgrowths indicated no consistent selective effect of any of the individual matrix components either on endocrine activity [unreadable] or outgrowth proliferation. We conclude that signaling pathways promoting differentiation are not restricted to specific [unreadable] integrin-ligand interactions but may be convergent on a central mechanism regardless of the anchoring ligand and [unreadable] receptor. This research used WNPRC Research Services, including federally approved human ES cell lines.